/*******************ts.s************/
        .globl running, scheduler, tswitch
tswitch:
SAVE:	pushl	%eax	
		pushl	%ebx	
		pushl	%ecx	
		pushl	%edx	
		pushl	%ebp	
		pushl	%esi	
		pushl	%edi	
		pushfl	
		movl	running,%ebx	# ebx -> PROC
		movl	%esp, 4(%ebx)	# PORC.save_sp = esp
FIND:	call	scheduler	
RESUME:	movl	running,%ebx	# ebx -> PROC
		movl	4(%ebx),%esp	# esp = PROC.saved_sp
		popfl
		popl	%edi	
		popl	%esi	
		popl	%ebp	
		popl	%edx	
		popl	%ecx	
		popl	%ebx	
		popl	%eax	
		ret		
